It is known in the trucking industry to "spot" a trailer by decoupling the tractor from the trailer after the trailer is positioned at a loading dock. A kingpin is provided adjacent the front bottom portion of the trailer whose construction is well known in the art. Typically the tractor includes a biased coupling plate (fifth wheel) for latching engagement with the kingpin. However, with the trailer spotted, the kingpin is exposed, and the front end of the trailer is thus unsupported.
Because of this lack of support, there are typically provided support members known as "landing gear" and disposed along the body of a trailer towards the front of a trailer. The landing gear is typically cranked down to engage the ground so as to enable the trailer to be disengaged from the tractor. The landing gear is then intended to remain in engagement with the ground to keep the trailer from toppling over.
When a spotted trailer is located at the dock if loaded in a conventional manner, for example by a fork truck, the fork truck may drive forward past the cranked down landing gear and hence risk toppling or "nose-diving" the trailer. Jack stands therefore may be provided adjacent the front of the trailer. However these are manually operated stands which are positioned near each edge of the front of the trailer before loading. Unless these jack stands engage the metal plate reinforcement surrounding the kingpin or engage the kingpin itself then there is the risk of the failure of the stand or the trailer during loading and resulting nose-diving of the trailer. For example if the jack stands engage the floor channel of the trailer, which channels may be corroded, or the wooden floor boards of the trailer, depending on the load distribution an accident may occur.
It would therefore be advantageous to provide a more substantial and preferably centrally disposed support for the trailer proximate the front end thereof, which support would engage adjacent to the metal plate reinforcement surrounding the kingpin or engage the kingpin itself, which pin is normally engaged by the tractor, and thereby prevent the trailer from nose-diving or alternatively tail diving (if the rear wheels of the trailer are positioned so as to provide a considerable overhang toward the rear of the trailer) during normal loading.
U.S. Pat. No. 5,165,265 provides, in combination with a security lock, support legs for engaging the support surface adjacent the forward end of an associated trailer.
U.S. Pat. No. 4,014,517 describes one example of a stand for supporting a structure such as a mobile home above the ground. The stand includes a flat broad base for engaging the ground and a plurality of legs assembled to the base. The legs converge from the base to a support 22 so that the support platform may be positioned in a firm supportive relationship to the structure. Manual operation of a handle 63 provides for the hydraulic jacking of the support 22 to engage a structural member of the mobile home or the like.
U.S. Pat. No. 4,169,579 provides a support assembly for supporting a tongue of a trailer and adjustable to establish the tongue at a desired elevation from the ground so as to enhance hitching to a towing vehicle.
Nowhere in the prior art is there provided a collapsible, (for example folding), safety stand for engagement in one position, for example to the kingpin of an unfettered or spotted trailer or the like or that may be positioned adjacent the kingpin of the trailer proximate the reinforcing plate provided with the kingpin to provide prevention of nose-diving of the trailer during loading or unloading and which safety device may be alternatively positioned in a flat stored position to allow a tractor access for hitching the trailer.
It is therefore a primary object of the invention to provide a collapsible (for example folding), trailer safety stand which is located in the bay in which a trailer is normally docked.
It is a further object of the invention to provide a collapsible (for example folding), safety stand which has a portion which engages adjacent to or to the kingpin of an unfettered or spotted trailer, which is normally engaged by a tractor when locating the trailer in a docked position.
It is yet a further object of the invention to provide a collapsible (for example folding), safety stand which has a moveable portion which engages adjacent to, or to the kingpin of an unfettered or spotted trailer, which is normally engaged by a tractor when locating the trailer in the docked position. The moveable portion may further accommodate various lengths of trailers.
Further and other objects of the invention will become apparent to those skilled in the art when considering the following summary of the invention and the more detailed description of the preferred embodiments illustrated herein.